Draft stabilizer for stove flue pipes



JuHy 17, 1934.

E. v. COULSTON l9966,5346

DRAFT STABILIZER FOR STOVE FLUE PIPES Filed Feb. 18, 1932 W "5 k EXCESSme 14 WASTE 4 #1 i Peooucra AWBWOQ: 1 76; 2 [21,04 L/ (001570 5y M QMJPatented July 17, 1934 UNITED STATES ATENT FFHCE DRAFT STABILIZER FORSTOVE FLUE PIPES 7 Claims.

My invention particularly relates to draft stabilizers whichautomatically control the draft through the flue pipes of stoves, whichprevent variations of chimney draft from afiecting the stove connectedto the chimney, which insure a safe and sure lighting and starting ofstoves when atmospheric conditions have temporarily blanketed andstopped the chimney draft, and which effect the desired draft controlwithout at any time shutting off the full free passage of the stoveswaste products to the chimney. My improved stabilizer can be made at lowcost and readily installed on any stove without the use of specialtools. Although my invention is adaptable for use with stoves burningall types of fuel, it is particularly adapted for use with stovesburning gas or similar fuel.

Gas burning stoves when set up for operation should be connected bymeans of flue pipes to a chimney which will discharge the waste productsoutside of the building. In fact, such method of operation is requiredby ordinance in most municipalities. The use of these fines and chimneysrequires a waste product and air conducting system which is verysensitive to atmospheric and other changes. Hot and muggy outdoorsweather, cold and snappy outside weather, strength and direction ofWinds, all affect the stove operation, when exposed to these differentweather conditions through the medium of the connecting pipes andchimneys. Thus the same stove with the same burner flame operates quitedifierently and gives widely differing results at different times. Myinvention is designed to equalize these different conditions andstabilize the stove operation.

The annexed drawing and the following description set forth in detailcertain means embodying my invention, such disclosed means constituting,however, only one of the various forms to which the principle of theinvention may be embodied.

In said annexed drawing:

Figure 1 is a partial plan view and a partial plan section of myimproved stabilizer, taken in the planes indicated by the line 11,Figure 2; and

Figure 2 is a central vertical section of the stabilizer incorporatedwithin and between adjacent sections of a stove flue pipe, fragmentaryportions of which are shown in the view, the plane of the section beingindicated by the line 2--2, Figure 1.

Referring to the annexed drawing in which the same parts are indicatedby the same respective numbers in the several views, the stabilizercomprises a lower ring section 1 which forms a central circular inletopening for waste products from the stove, which are conducted theretothrough the stove pipe 2 upon the upper end of which the ring 1 ismounted with a snug fit, the ring 1 having an inside annular flange 3forming a stop for the pipe 2 when it has entered to its properposition. The ring 1 is connected to a larger and concentric ring 6 bymeans of an annular series of spaced ribs 4 which are connected to, andextend upwardly and outwardly from, the ring 1, so that there is formedan annular series of spaced openings 5 through the body of thestabilizer shell member formed by the rings 1 and 6, these openings 5communicating with the atmosphere outside of the stove pipe 2. The ring1, ribs 4, and ring 6 may be separate members suitably secured togetheror any two of them may be integrally formed, but I prefer to form allthree members as one integral body.

The stabilizer further includes an upper shell 7 which is a dome-likemember erected upon the lower shell ring 6 and forming a continuous bodytherewith, this dome-like shell having an upper annular flange 8,preferably of substantially the shape and size of the lower ring 1, andforming an outlet opening from the stabilizer opposite the lower inlet,this flange 8 being adapted to be inserted within the lower end of aflue pipe section 9.

Between the inlet and outlet of the stabilizer and spaced from the wallthereof so as to form an annular continuous passage adjacent said wallis a draft-baffling member 10 of substantially the shape and area of theinlet opening through the lower ring 1. This member 10 may be suitablysupported in any desired manner but, as shown in the accompanyingdrawing, depends from the flange 8 of the upper domelike shell by meansof spaced ribs 11 integrally formed with the flange 8 and member 10, the

upper and lower shells being connected together by bolts 13 which arepassed through the draftbaffling member 10 and inwardly-extended lugs 14formed integrally with the flange 3 of the lower ring 1. Thedraft-baffling member 10 is centrally located relatively to the Wall ofthe stabilizer and so spaced from the Wall thereof as to provide anannular draft passage 12 around the baffling member of an area at leastas great as the area of the inlet opening through the ring 1. Theopenings 5 through the lower stabilizer Y shell communicate with theannular draft passage l2 and are substantially longitudinally alignedtherewith. The draft-baflling member 10 may be formed, and is so shownin the accompanying drawing, with a central opening 15 which serves asan inspirator, in the manner and for the purpose hereinafter fullydescribed.

When installing the above-described stabilizer, it is necessary only toslip the lower ring 1 over the top end of the first joint of stove pipeleading from a stove and then to slip the bottom end of the second stovepipe joint over the flange 8 of the upper stabilizer shell. Therefore notools are required in the installation of the device, and any one caninstall it with very little inconvenience.

In order to describe the operation of the stabilizer, it may be statedthat when a stove is set up and operated without any flue connection,and its waste products simply flow out of the upper stove opening, thestove will operate properly and satisfactorily, if the disposition ofthe waste products is disregarded. Under these conditions the stove willalways operate at the same draft rate, which does not vary because it isnot subject to outside influences. This may be called a normal draftrate and is the rate at which the stove should operate for uniformresults and highest efficiency. My invention causes the stove to sooperate at all times even when subject to the conditions incident toflue and chimney connection, as will now be described.

If the weather conditions are such as to cause a strong draft with arapid rate of draft speed, its effect is prevented from extending downinto the stove by reason of the interposed baflieplate 10. Diverted bythe baffle plate 10, the strong draft exerts itself on the annularpassage 12 and is thus brought in line with the openings 5 to theatmosphere outside of the lower flue pipe. Thus air is drawn into thestabilizer from the room and is pulled up the chimney. Meanwhile thenormal draft of the stove delivers. waste products below the bafilemember 10, and these products spread out under the bafiie member 10 tothe edge of the latter and reach the draft passage 12. Here theyjarecaughtup by the chimney action. Inasmuch as these waste products arehot, they arefirst to flow up around the baffle plate 10 and to thechimney above, to the exclusion of that much room air through theopenings 5. The combined air supply'through the openings 5 and the wasteproducts always balance the chimney demand.

' If the weather conditions are such that there is no chimney pull oreven a slightly descending current and which with a stove as ordinarilyconnected to a pipe might require a relighting two orthree times beforethe stove burns properly, then the descending current is stopped by thebaffle plate 10 from affecting the stove below. This current spreads tothe sides of the baflie plate 10, and flows down through the annularpassage 12 and out into the room through the openings 5. At the sametime the'stove by its normal draft delivers the hot waste products underthe baflle plate 10 whence they spread to the sides thereof and for afew moments may to an extent be entrained by the down draft and alsoflow outinto the room through the openings 5. But the stove continues toburn freely, the flame not being blanketed and extinguished by thedescending current of air, so that in a few moments the heat of thewaste products start the draft movement upward above the baflie plate 10and through the chimney. By means of the inspirator opening 15 shown anddescribed, this reversal of draft movement may be accelerated.

In neither of the opposite extremes above described does the chimneydraft exert any undue action on the stove itself. The chimney acts onlyon what is delivered to the annular passage 12 at the edge of the baflleplate 10. It is evident that the same action in varying degrees takesplace incident to the many graduated conditions between the describedextremes. Also incident to these operations, is the diverting of anyback draft occurring for a few minutes from a wind puff, withoutaffecting the stove burner, and the impossibility of any extra strongchimney draft whipping heat through and out of the stove oven fasterthan the normal rate of operation produces heat. Also, no adverse draftcan have any smothering effect upon the stove burners.

I direct particular attention to the fact that my stabilizer actsautomatically and requires no regulation, that it has no moving partswhich would wear and require attention, that it is noiseless, and thatat all times it provides a full free passage for all of the products ofcombustion from the stove to the chimney.

What I claim is:

1.. A draft stabilizer for stove flue. pipes comprising a cylindricalshell in two sections, one of which is formed with an inlet opening andthe other with an outlet opening, a draftbaffling member within andspaced from the wall of the shell to form a tortuous continuous draftpassage around the baffling member from the inlet to the outlet, saiddraft-bafiling member being integrally formed with one of the shellsections, the shell being formed with an annular series of openingssurrounding the inlet opening and communicating with said draft passage,and said draft-baffling member being formed with an inspirator openingtherethrough.

2. A draft stabilizer for stove flue pipes comprising a lower. shellhaving concentric cylindrical sections integrally connected by anannular series of ribs so as to form a series of openings between thesections, the inner shell section being formed with an inlet opening, anuppercylindrical shell erected on the outer section of the lower shelland having an outlet opening, and a draft-baffling member integrallyformed with the upper shell andrigidly secured to the lower shell andinterposed between the inlet and outlet and spaced from the shell wallsto form a draft passage around said member from the inlet to the outlet,said draft passage communicating with said series of openings.

3. A draft stabilizer for stove flue pipes comprising a lower shellhaving concentric cylindrical sections integrally connected by anannular series of ribs so as to form a series-of openings between thesections, the inner shell section being formed with an inlet opening, anupper cylindrical shell erected on the outer section of the lower shelland having an-outlet opening, and a draft-baffling member integrallyformed with the upper shell and rigidly secured to the lower shell andinterposed between the inlet and outlet and spaced from the shell wallsto form a draft passage around said member from the inlet to the outlet,said draft passage communicating with said series of openings, and saiddraft-baffling member being formed with an inspirator openingtherethrough.

4. A draft stabilizer for stove flue pipes comprising a lower shellhaving concentric cylindrical sections integrally connected by anannular series of ribs so as to form a series of openings between thesections, the inner shell section having a depending flange adapted totelescope with a flue section, an upper cylindrical shell erected on theouter section of the lower sheil and having an upwardly-extended flangeof substantially the same diameter as said depending flange and adaptedto telescope with a flue section, said shells being rigidly secured.together, said shells having, respectively, inlet and out-let openingscommunicating with the interiors of said flanges, and a draft-baiiiingmember supported by said shells between the inlet and outlet and spacedwithin and from the stabilizer wall to form a draft passage around saidmember from the inlet to the outlet, said draft passage communicatingwith said series of openings between the ribs, and said draft-haulingmember being formed with an inspirator opening therethrough.

5. A draft stabilizer for stove flue pipes comprising a lower shellhaving a central annular ring member forming a circular inlet, said ringhaving a depending flange adapted to telescope with a flue section, anannular series of outwardly-extended spaced ribs integrally formed withsaid ring, and an outer ring to which the outer ends of said ribs areintegrally joined, an upper dome-shaped shell erected on said outer ringand having a central outlet opening opposite said inlet, said uppershell having an upwardly-extended flange of substantially the samediameter as said depending flange and adapted to telescope with a fluesection, and a draft-baiiiing member integrally formed with one shelland rigidly secured to the other shell and mounted within andsymmetrically relative to the shell walls and spaced from said walls toform a tortuous draft passage from the inlet to the outlet, said draftpassage communicating with the spaces between said ribs.

6. A draft stabilizer for stove flue pipes comprising a lower shellhaving a central annular ring member forming a circular inlet, anannular series of outwardly-extended spaced ribs integrally formed withsaid ring, and an outer ring to which the outer ends of said ribs areintegraliy joined, an upper dome-shaped shell erected on said outer ringand having a central outlet opening opposite said inlet, and adraft-bailing member integrally formed with one shell and rigidlysecured to the other shell and mounted within and symmetricaly relativeto the shell walls and spaced from said walls to form a tortuous draftpassage from the inlet to the outlet, said draft passage communicatingwith the spaces between said ribs, and said draftbaifiing member beingformed with a central inspirator opening therethrough.

7. A draft stabilizer for stove flue pipes comprising a lower shellhaving inner and outer sec tions integrally connected by a series ofspaced ribs so as to form a series of openings between the sections, theinner shell section being formed with an inlet opening, an upper shellerected on the outer section of the lower shell and having an outletopening, and a draft-baffling member integrally formed with one of theshells and rigidly secured to the other shell and interposed between theinlet and outlet and spaced from the shell walls to form a draft passagearound said member from the inlet to the outlet, said draft passagecommunicating with said series of openings.

EARL V. COULSTON.

